如何将相机参数持久化到SharedPreferences中？

Question

如何在活动销毁后保留相机的复选框状态和设置？

或者换句话说，如何将相机参数持久化到SharedPreferences中？

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.menu_old);
SharedPreferences preferences = 
getSharedPreferences("PREFS_NAME",MODE_WORLD_READABLE);

yourCheckBox = (CheckBox) findViewById( R.id.fonarb );
yourCheckBox.setChecked(preferences.getBoolean("lol",false));
yourCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener()

{
@Override
public void onCheckedChanged(CompoundButton   yourCheckBox,
        boolean isChecked) {
     if (isChecked){

         Parameters params = camera.getParameters();
         params.setColorEffect(Parameters.EFFECT_NEGATIVE);
         camera.setParameters(params);


     }
     else {     
         Parameters params = camera.getParameters();
         params.setColorEffect(Parameters.EFFECT_NONE);
         camera.setParameters(params);

     }

}


});

public void onStop(){
 SharedPreferences settings = getSharedPreferences("PREFS_NAME", MODE_WORLD_READABLE);
 SharedPreferences.Editor editor = settings.edit();
 editor.putBoolean("lol", true);


 editor.commit();
 super.onStop();
}

---

照你说的做了，不想保存设置！ :(

    SharedPreferences preferences = getSharedPreferences("qwe",MODE_PRIVATE);
    yourCheckBox = (CheckBox) findViewById( R.id.fonarb );
    yourCheckBox.setChecked(preferences.getBoolean("lol",false));
    yourCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener()

    {
    @Override
    public void onCheckedChanged(CompoundButton   yourCheckBox,
            boolean isChecked) {
         if (isChecked){

             Parameters params = camera.getParameters();
             params.setColorEffect(Parameters.EFFECT_NEGATIVE);
             camera.setParameters(params);



         }
         else {     
             Parameters params = camera.getParameters();
             params.setColorEffect(Parameters.EFFECT_NONE);
             camera.setParameters(params);

         }

    }


    });









    protected void onPause()

   {
        SharedPreferences settings = getSharedPreferences("qwe",MODE_PRIVATE);
    SharedPreferences.Editor editor = settings.edit();
    yourCheckBox = (CheckBox) findViewById( R.id.fonarb );
    editor.putBoolean("lol", yourCheckBox.isChecked());
    editor.commit();
        super.onPause();
     }

Answer 1

不要总是在 SharedPreferences 中存储“true”，只需存储 CheckBox 的当前状态即可。

SharedPreferences settings = getSharedPreferences("PREFS_NAME", MODE_WORLD_READABLE);
SharedPreferences.Editor editor = settings.edit();
CheckBox yourCheckBox = (CheckBox) findViewById( R.id.fonarb );
editor.putBoolean("lol", yourCheckBox.isChecked());
editor.commit();

您还可以考虑将此代码移至 onPause() 而不是 onStop()。操作系统（Honeycomb 之前的版本）可以在活动暂停后终止您的活动，而无需调用 onStop()。如果发生这种情况，您的 SharedPreferences 将不会被保存。